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Elliott JE, Brewer JS, Keil AT, Ligman BR, Bryant-Ekstrand MD, McBride AA, Powers K, Sicard SJ, Twamley EW, O’Neil ME, Hildebrand AD, Nguyen T, Morasco BJ, Gill JM, Dengler BA, Lim MM. Feasibility and acceptability for LION, a fully remote, randomized clinical trial within the VA for light therapy to improve sleep in Veterans with and without TBI: An MTBI 2 sponsored protocol: LION: A remote RCT protocol within VA. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.30.24308195. [PMID: 38853958 PMCID: PMC11160858 DOI: 10.1101/2024.05.30.24308195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Sleep-wake disturbances frequently present in Veterans with mild traumatic brain injury (mTBI). These TBI-related sleep impairments confer significant burden and commonly exacerbate other functional impairments. Therapies to improve sleep following mTBI are limited and studies in Veterans are even more scarce. In our previous pilot work, morning bright light therapy (MBLT) was found to be a feasible behavioral sleep intervention in Veterans with a history of mTBI; however, this was single-arm, open-label, and non-randomized, and therefore was not intended to establish efficacy. The present study, LION (light vs ion therapy) extends this preliminary work as a fully powered, sham-controlled, participant-masked randomized controlled trial (NCT03968874), implemented as fully remote within the VA (target n=120 complete). Randomization at 2:1 allocation ratio to: 1) active: MBLT (n=80), and 2) sham: deactivated negative ion generator (n=40); each with identical engagement parameters (60-min duration; within 2-hrs of waking; daily over 28-day duration). Participant masking via deception balanced expectancy assumptions across arms. Outcome measures were assessed following a 14-day baseline (pre-intervention), following 28-days of device engagement (post-intervention), and 28-days after the post-intervention assessment (follow-up). Primary outcomes were sleep measures, including continuous wrist-based actigraphy, self-report, and daily sleep dairy entries. Secondary/exploratory outcomes included cognition, mood, quality of life, circadian rhythm via dim light melatonin onset, and biofluid-based biomarkers. Participant drop out occurred in <10% of those enrolled, incomplete/missing data was present in <15% of key outcome variables, and overall fidelity adherence to the intervention was >85%, collectively establishing feasibility and acceptability for MBLT in Veterans with mTBI.
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Affiliation(s)
- Jonathan E. Elliott
- VA Portland Health Care System, Portland, OR, USA
- Oregon Health & Science University, Department of Neurology, Portland, OR, USA
- Military Traumatic Brain Injury Initiative (MTBI), Bethesda, MD, USA
- VISN 20 Northwest Mental Illness Research, Education and Clinical Center (MIRECC), VA Puget Sound Health Care System, Seattle, WA, USA
| | | | | | | | | | | | | | | | - Elizabeth W. Twamley
- VA San Diego Health Care System, Research Service; Center of Excellence for Stress and Mental Health, San Diego, CA, USA
- University of California San Diego, Department of Psychiatry, La Jolla, CA, USA
| | - Maya E. O’Neil
- VA Portland Health Care System, Portland, OR, USA
- VISN 20 Northwest Mental Illness Research, Education and Clinical Center (MIRECC), VA Puget Sound Health Care System, Seattle, WA, USA
- Oregon Health & Science University, Medical Informatics and Clinical Epidemiology, Portland, OR, USA
- Oregon Health & Science University, Department of Psychiatry, Portland, OR, USA
| | - Andrea D. Hildebrand
- Oregon Health & Science University – Portland State University, School of Public Health, Biostatistics & Design Program, Portland, OR, USA
| | - Thuan Nguyen
- Oregon Health & Science University – Portland State University, School of Public Health, Biostatistics & Design Program, Portland, OR, USA
| | - Benjamin J. Morasco
- VA Portland Health Care System, Portland, OR, USA
- VISN 20 Northwest Mental Illness Research, Education and Clinical Center (MIRECC), VA Puget Sound Health Care System, Seattle, WA, USA
- Oregon Health & Science University, Department of Psychiatry, Portland, OR, USA
| | - Jessica M. Gill
- John’s Hopkins University, School of Nursing, Baltimore, MD, USA
| | | | - Miranda M. Lim
- VA Portland Health Care System, Portland, OR, USA
- Oregon Health & Science University, Department of Neurology, Portland, OR, USA
- Military Traumatic Brain Injury Initiative (MTBI), Bethesda, MD, USA
- VISN 20 Northwest Mental Illness Research, Education and Clinical Center (MIRECC), VA Puget Sound Health Care System, Seattle, WA, USA
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Srisurapanont K, Samakarn Y, Kamklong B, Siratrairat P, Bumiputra A, Jaikwang M, Srisurapanont M. Efficacy and acceptability of blue-wavelength light therapy for post-TBI behavioral symptoms: A systematic review and meta-analysis of randomized controlled trials. PLoS One 2022; 17:e0274025. [PMID: 36201498 PMCID: PMC9536631 DOI: 10.1371/journal.pone.0274025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/20/2022] [Indexed: 11/07/2022] Open
Abstract
Objective Behavioral symptoms are common after traumatic brain injury (TBI), but their treatments remain unsatisfactory. This systematic review and meta-analysis compared the efficacy and acceptability between blue-wavelength light therapy (BWLT) and long-wavelength/no light therapy (LW/NLT) for post-TBI sleepiness, sleep disturbance, depressive symptoms, and fatigue. Methods This study included randomized controlled trials comparing the effects of BWLT and LW/NLT on post-TBI sleepiness, sleep disturbance, depression, or fatigue. We searched Pubmed, Embase, CINAHL, and Cochrane Central Register of Controlled of Trials on April 13, 2022. The revised tool for assessing the risk of bias in randomized trials was applied. We performed a frequentist pairwise meta-analysis using a random-effects model. Results Of 233 retrieved records, six trials (N = 278) were included in this meta-analysis. TBIs ranged from mild to severe, and the interventions were administered for a median of 35 days. Most trials delivered light therapy via lightboxes. Three trials had a high risk of bias. BWLT was significantly superior to LW/NLT in reducing sleep disturbance (5 trials; SMD = -0.63; 95% CI = -1.21 to -0.05; p = 0.03; I2 = 61%) and depressive symptoms (4 trials; SMD = -1.00; 95% CI = -1.62 to -0.38; p < 0.01; I2 = 56%). There were trends that BWLT was superior to LW/NLT in reducing sleepiness (6 trials; SMD = -0.92; 95% CI = -1.84 to 0.00; p = 0.05; I2 = 88%) and fatigue (4 trials; SMD = -1.44; 95% CI = -2.95 to 0.08; p = 0.06; I2 = 91%). All-cause dropout rates were not significantly different between groups. Conclusion Limited and heterogenous evidence suggests that short-term BWLT is well accepted, has a large treatment effect on post-TBI depressive symptoms, and may have a moderate treatment effect on post-TBI sleep disturbance.
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Affiliation(s)
| | - Yanisa Samakarn
- Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | | | - Arina Bumiputra
- Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Montita Jaikwang
- Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Manit Srisurapanont
- Department of Psychiatry, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- * E-mail:
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Killgore WDS, Vanuk JR, Dailey NS. Treatment with morning blue light increases left amygdala volume and sleep duration among individuals with posttraumatic stress disorder. Front Behav Neurosci 2022; 16:910239. [PMID: 36172470 PMCID: PMC9510679 DOI: 10.3389/fnbeh.2022.910239] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 08/24/2022] [Indexed: 01/18/2023] Open
Abstract
BackgroundPosttraumatic stress disorder (PTSD) is associated with numerous cognitive, affective, and psychophysiological outcomes, including problems with sleep and circadian rhythms. We tested the effectiveness of a daily morning blue-light exposure treatment (BLT) versus a matched amber light treatment (ALT) to regulate sleep in individuals diagnosed with PTSD. Moreover, PTSD is also associated with reliable findings on structural neuroimaging scans, including reduced amygdala volumes and other differences in cortical gray matter volume (GMV) that may be indicative of underlying neurobehavioral dysfunctions. We examined the effect of BLT versus ALT on GMV and its association with sleep outcomes.MethodsSeventy-six individuals (25 male; 51 female) meeting DSM-V criteria for PTSD (Age = 31.45 years, SD = 8.83) completed sleep assessments and structural neuroimaging scans, followed by random assignment one of two light groups, including BLT (469 nm; n = 39) or placebo ALT (578 nm; n = 37) light therapy daily for 30-min over 6-weeks. Participants wore a wrist actigraph for the duration of the study. After treatment, participants returned to complete sleep assessments and a structural neuroimaging scan. Neuroimaging data were analyzed using the Computational Anatomy Toolbox (CAT12) and Voxel-Based Morphometry (VBM) modules within the Statistical Parametric Mapping (SPM12) software.ResultsThe BLT condition produced significant increases in total time in bed and total sleep time from actigraphy compared to the ALT condition, while ALT improved wake after sleep onset and sleep efficiency compared to BLT. Additionally, BLT led to an increase in left amygdala volume compared to ALT but did not affect hypothesized medial prefrontal regions. Finally, within group correlations showed that improvements in sleep quality and nightmare severity were correlated with increases in left amygdala volume over the course of treatment for the BLT group but not the ALT group.ConclusionIn individuals with PTSD, daily exposure to morning blue light treatment was associated with improvements in objective sleep duration and increased volume of the left amygdala compared to amber placebo light treatment, and changes in amygdala volume correlated with subjective improvement in sleep. These findings suggest that daily morning BLT may provide an important non-pharmacologic adjunctive approach for facilitating sleep and neurobehavioral recovery from PTSD.
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Elliott JE, Tinsley CE, Reynolds C, Olson RJ, Weymann KB, Au-Yeung WTM, Wilkerson A, Kaye JA, Lim MM. Tunable White Light for Elders (TWLITE): A Protocol Demonstrating Feasibility and Acceptability for Deployment, Remote Data Collection, and Analysis of a Home-Based Lighting Intervention in Older Adults. SENSORS 2022; 22:s22145372. [PMID: 35891052 PMCID: PMC9320387 DOI: 10.3390/s22145372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 06/25/2022] [Accepted: 07/11/2022] [Indexed: 12/10/2022]
Abstract
Sleep disturbances are common in older adults and may contribute to disease progression in certain populations (e.g., Alzheimer's disease). Light therapy is a simple and cost-effective intervention to improve sleep. Primary barriers to light therapy are: (1) poor acceptability of the use of devices, and (2) inflexibility of current devices to deliver beyond a fixed light spectrum and throughout the entirety of the day. However, dynamic, tunable lighting integrated into the native home lighting system can potentially overcome these limitations. Herein, we describe our protocol to implement a whole-home tunable lighting system installed throughout the homes of healthy older adults already enrolled in an existing study with embedded home assessment platforms (Oregon Center for Aging & Technology-ORCATECH). Within ORCATECH, continuous data on room location, activity, sleep, and general health parameters are collected at a minute-to-minute resolution over years of participation. This single-arm longitudinal protocol collected participants' light usage in addition to ORCATECH outcome measures over a several month period before and after light installation. The protocol was implemented with four subjects living in three ORCATECH homes. Technical/usability challenges and feasibility/acceptability outcomes were explored. The successful implementation of our protocol supports the feasibility of implementing and integrating tunable whole-home lighting systems into an automated home-based assessment platform for continuous data collection of outcome variables, including long-term sleep measures. Challenges and iterative approaches are discussed. This protocol will inform the implementation of future clinical intervention trials using light therapy in patients at risk for developing Alzheimer's disease and related conditions.
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Affiliation(s)
- Jonathan E. Elliott
- VA Portland Health Care System, Research Service, Portland, OR 97239, USA; (J.E.E.); (C.E.T.); (R.J.O.)
- Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA; (C.R.); (W.-T.M.A.-Y.); (J.A.K.)
| | - Carolyn E. Tinsley
- VA Portland Health Care System, Research Service, Portland, OR 97239, USA; (J.E.E.); (C.E.T.); (R.J.O.)
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA
| | - Christina Reynolds
- Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA; (C.R.); (W.-T.M.A.-Y.); (J.A.K.)
| | - Randall J. Olson
- VA Portland Health Care System, Research Service, Portland, OR 97239, USA; (J.E.E.); (C.E.T.); (R.J.O.)
| | | | - Wan-Tai M. Au-Yeung
- Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA; (C.R.); (W.-T.M.A.-Y.); (J.A.K.)
| | | | - Jeffrey A. Kaye
- Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA; (C.R.); (W.-T.M.A.-Y.); (J.A.K.)
| | - Miranda M. Lim
- Department of Neurology, Oregon Health & Science University, Portland, OR 97239, USA; (C.R.); (W.-T.M.A.-Y.); (J.A.K.)
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239, USA
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, USA
- Pulmonary and Critical Care Medicine, Oregon Health & Science University, Portland, OR 97239, USA
- VA Portland Health Care System, Mental Illness Research Education and Clinical Center, Neurology, National Center for Rehabilitative Auditory Research, Portland, OR 97239, USA
- Correspondence: ; Tel.: +1-503-220-8262 (ext. 57404)
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Feasibility and preliminary efficacy for morning bright light therapy to improve sleep and plasma biomarkers in US Veterans with TBI. A prospective, open-label, single-arm trial. PLoS One 2022; 17:e0262955. [PMID: 35421086 PMCID: PMC9009710 DOI: 10.1371/journal.pone.0262955] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 12/20/2021] [Indexed: 11/19/2022] Open
Abstract
Mild traumatic brain injury (TBI) is associated with persistent sleep-wake dysfunction, including insomnia and circadian rhythm disruption, which can exacerbate functional outcomes including mood, pain, and quality of life. Present therapies to treat sleep-wake disturbances in those with TBI (e.g., cognitive behavioral therapy for insomnia) are limited by marginal efficacy, poor patient acceptability, and/or high patient/provider burden. Thus, this study aimed to assess the feasibility and preliminary efficacy of morning bright light therapy, to improve sleep in Veterans with TBI (NCT03578003). Thirty-three Veterans with history of TBI were prospectively enrolled in a single-arm, open-label intervention using a lightbox (~10,000 lux at the eye) for 60-minutes every morning for 4-weeks. Pre- and post-intervention outcomes included questionnaires related to sleep, mood, TBI, post-traumatic stress disorder (PTSD), and pain; wrist actigraphy as a proxy for objective sleep; and blood-based biomarkers related to TBI/sleep. The protocol was rated favorably by ~75% of participants, with adherence to the lightbox and actigraphy being ~87% and 97%, respectively. Post-intervention improvements were observed in self-reported symptoms related to insomnia, mood, and pain; actigraphy-derived measures of sleep; and blood-based biomarkers related to peripheral inflammatory balance. The severity of comorbid PTSD was a significant positive predictor of response to treatment. Morning bright light therapy is a feasible and acceptable intervention that shows preliminary efficacy to treat disrupted sleep in Veterans with TBI. A full-scale randomized, placebo-controlled study with longitudinal follow-up is warranted to assess the efficacy of morning bright light therapy to improve sleep, biomarkers, and other TBI related symptoms.
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Daily Morning Blue Light Therapy Improves Daytime Sleepiness, Sleep Quality, and Quality of Life Following a Mild Traumatic Brain Injury. J Head Trauma Rehabil 2021; 35:E405-E421. [PMID: 32472836 DOI: 10.1097/htr.0000000000000579] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Identify the treatment effects of 6 weeks of daily 30-minute sessions of morning blue light therapy compared with placebo amber light therapy in the treatment of sleep disruption following mild traumatic brain injury. DESIGN Placebo-controlled randomized trial. PARTICIPANTS Adults aged 18 to 45 years with a mild traumatic brain injury within the past 18 months (n = 35). MAIN OUTCOME MEASURES Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Beck Depression Inventory II, Rivermead Post-concussion Symptom Questionnaire, Functional Outcomes of Sleep Questionnaire, and actigraphy-derived sleep measures. RESULTS Following treatment, moderate to large improvements were observed with individuals in the blue light therapy group reporting lower Epworth Sleepiness Scale (Hedges' g = 0.882), Beck Depression Inventory II (g = 0.684), Rivermead Post-concussion Symptom Questionnaire chronic (g = 0.611), and somatic (g = 0.597) symptoms, and experiencing lower normalized wake after sleep onset (g = 0.667) than those in the amber light therapy group. In addition, individuals in the blue light therapy group experienced greater total sleep time (g = 0.529) and reported improved Functional Outcomes of Sleep Questionnaire scores (g = 0.929) than those in the amber light therapy group. CONCLUSION Daytime sleepiness, fatigue, and sleep disruption are common following a mild traumatic brain injury. These findings further substantiate blue light therapy as a promising nonpharmacological approach to improve these sleep-related complaints with the added benefit of improved postconcussion symptoms and depression severity.
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Bajaj S, Raikes AC, Razi A, Miller MA, Killgore WDS. Blue-Light Therapy Strengthens Resting-State Effective Connectivity within Default-Mode Network after Mild TBI. J Cent Nerv Syst Dis 2021; 13:11795735211015076. [PMID: 34104033 PMCID: PMC8145607 DOI: 10.1177/11795735211015076] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 02/08/2021] [Indexed: 11/15/2022] Open
Abstract
Background: Emerging evidence suggests that post concussive symptoms, including mood changes, may be improved through morning blue-wavelength light therapy (BLT). However, the neurobiological mechanisms underlying these effects remain unknown. We hypothesize that BLT may influence the effective brain connectivity (EC) patterns within the default-mode network (DMN), particularly involving the medial prefrontal cortex (MPFC), which may contribute to improvements in mood. Methods: Resting-state functional MRI data were collected from 41 healthy-controls (HCs) and 28 individuals with mild traumatic brain injury (mTBI). Individuals with mTBI also underwent a diffusion-weighted imaging scan and were randomly assigned to complete either 6 weeks of daily morning BLT (N = 14) or amber light therapy (ALT; N = 14). Advanced spectral dynamic causal modeling (sDCM) and diffusion MRI connectometry were used to estimate EC patterns and structural connectivity strength within the DMN, respectively. Results: The sDCM analysis showed dominant connectivity pattern following mTBI (pre-treatment) within the hemisphere contralateral to the one observed for HCs. BLT, but not ALT, resulted in improved directional information flow (ie, EC) from the left lateral parietal cortex (LLPC) to MPFC within the DMN. The improvement in EC from LLPC to MPFC was accompanied by stronger structural connectivity between the 2 areas. For the BLT group, the observed improvements in function and structure were correlated (at a trend level) with changes in self-reported happiness. Conclusions: The current preliminary findings provide empirical evidence that morning short-wavelength light therapy could be used as a novel alternative rehabilitation technique for mTBI. Trial registry: The research protocols were registered in the ClinicalTrials.gov database (CT Identifiers NCT01747811 and NCT01721356).
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Affiliation(s)
- Sahil Bajaj
- Social, Cognitive and Affective Neuroscience (SCAN) Laboratory, Department of Psychiatry, College of Medicine, University of Arizona, Tucson, AZ, USA
- Multimodal Clinical Neuroimaging Laboratory (MCNL), Center for Neurobehavioral Research, Boys Town National Research Hospital, Boys Town, NE, USA
- Sahil Bajaj, Multimodal Clinical Neuroimaging Laboratory, Center for Neurobehavioral Research, Boys Town National Research Hospital, 14015 Flanagan Blvd. Suite #102, Boys Town, NE 68010, USA.
| | - Adam C Raikes
- Center for Innovation in Brain Science, University of Arizona, Tucson, AZ, USA
| | - Adeel Razi
- Turner Institute for Brain and Mental Health, School of Psychological Sciences, and Monash Biomedical Imaging at Monash University, Clayton, VIC, Australia
- The Wellcome Centre for Human Neuroimaging, University College London, London, UK
- Department of Electronic Engineering, NED University of Engineering and Technology, Karachi, Pakistan
| | - Michael A Miller
- Social, Cognitive and Affective Neuroscience (SCAN) Laboratory, Department of Psychiatry, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - William DS Killgore
- Social, Cognitive and Affective Neuroscience (SCAN) Laboratory, Department of Psychiatry, College of Medicine, University of Arizona, Tucson, AZ, USA
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A Look Ahead. Concussion 2020. [DOI: 10.1016/b978-0-323-65384-8.00015-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2023] Open
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A randomized, double-blind, placebo-controlled trial of blue wavelength light exposure on sleep and recovery of brain structure, function, and cognition following mild traumatic brain injury. Neurobiol Dis 2019; 134:104679. [PMID: 31751607 DOI: 10.1016/j.nbd.2019.104679] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/20/2019] [Accepted: 11/15/2019] [Indexed: 01/17/2023] Open
Abstract
Sleep and circadian rhythms are among the most powerful but least understood contributors to cognitive performance and brain health. Here we capitalize on the circadian resetting effect of blue-wavelength light to phase shift the sleep patterns of adult patients (aged 18-48 years) recovering from mild traumatic brain injury (mTBI), with the aim of facilitating recovery of brain structure, connectivity, and cognitive performance. During a randomized, double-blind, placebo-controlled trial of 32 adults with a recent mTBI, we compared 6-weeks of daily 30-min pulses of blue light (peak λ = 469 nm) each morning versus amber placebo light (peak λ = 578 nm) on neurocognitive and neuroimaging outcomes, including gray matter volume (GMV), resting-state functional connectivity, directed connectivity using Granger causality, and white matter integrity using diffusion tensor imaging (DTI). Relative to placebo, morning blue light led to phase-advanced sleep timing, reduced daytime sleepiness, and improved executive functioning, and was associated with increased volume of the posterior thalamus (i.e., pulvinar), greater thalamo-cortical functional connectivity, and increased axonal integrity of these pathways. These findings provide insight into the contributions of the circadian and sleep systems in brain repair and lay the groundwork for interventions targeting the retinohypothalamic system to facilitate injury recovery.
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